Lasers or other forms of coherent electromagnetic radiation (ER) today have numerous applications, such as applications for marking and guiding munitions, vehicles, determining distance (ranging), navigating, surveying, remote sensing, highlighting an object and so on. In response, laser warning receiver (LWR) systems have become important to detect and process laser emissions. Typically, a LWR is a passive system that detects incoming laser emissions and processes the incoming laser emissions for various parameters, such as range of the origin or source of the laser emissions to the LWR system, angle of arrival of the laser emissions, spectral content, etc. For example, it is common for military vehicles, such as planes, helicopters, ships, etc., to be equipped with a LWR system. LWR systems may also be used in civilian or commercial settings, such as for vehicle safety, mass transit, etc.
Currently, the known LWR's are limited in sensitivity, range, spectral coverage (e.g., range of wavelengths detectible by the LWR system), angular coverage, operating temperature, resolution, etc. Moreover, current LWR devices are large and/or bulky and consume large amounts of power. This makes the known LWR systems unsuitable for many applications in which they would otherwise be useful. Furthermore, the known LWR's are prone to false alarms due to ambient light and/or other sources of optical emissions, which are common in the environment.
Accordingly, there is a need for a wideband laser sensing system, which has high optical sensitivities (low optical input) and that are relatively immune to false alarms.